Neptunium: the essentials

Neptunium is a radioactive rare earth metal and has at least 3 allotropic forms. It is named for the planet Neptune. Np-237 is a by-product from nuclear reactors.

Table: basic information about and classifications of neptunium.

Neptunium: historical information

Neptunium was discovered by Edwin M. McMillan and P. H. Abelson at 1940 in USA. Origin of name: named after "the planet Neptune".

Neptunium was the first synthetic transuranium element of the actinide series. It was discovered by McMillan and Abelson in 1940 at Berkeley, California, USA, who bombarded uranium with neutrons produced from a cyclotron. It was the first synthetic transuranium (elements after uranium) element discovered.

Neptunium: physical properties

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Neptunium: orbital properties

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Isolation: coming soon!

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neptunium atomic number